The present invention relates generally to electrical connections. More particularly, the present invention relates to a concealed service poke-through device.
Much activity has been devoted to avoiding the necessity of using on-floor conduits for conveying electrical power and communication lines to floor locations which were not within the original architectural and electrical planning of a facility, such as a multi-floor concrete building. Such on-floor conduits are unsightly and may also pose a safety hazard to persons working in such area.
One technique for avoiding the use of on-floor conduits involves the drilling of a hole through the concrete floor at a desired location and the routing of power or communication lines beneath the floor and then up through the hole. Transition apparatus known as xe2x80x9cpoke-throughsxe2x80x9d have been developed for use in such interfloor holes. Such poke-throughs are subject to electrical and fire safety considerations. Among these are two fire-related requirements. First, the poke-through cannot function as a chimney or fire-advancing flue in the event of a fire on the lower floor. Second, the poke-through cannot function as a floor-to-floor heat conduction path.
These safety requirements have largely been met through the use of intumescent material. For example, co-assigned U.S. Pat. Nos. 5,003,127 and 5,107,072 disclose a poke-through assembly wherein a sheet of intumescent material is wired in place about a housing, and expands to fill and block the interfloor hole in the event of fire. Furthermore, thermally insulating materials have been interposed between metallic (and therefore heat conductive) portions of the poke-through devices. Thus, poke-through devices have come into common use.
With greater use of poke-through devices, there is, of course, interest in making their manufacturing economical, their installation easier and faster, and their retention more positive. The United States Patent of James H. Whitehead, entitled xe2x80x9cPoke-Through Electrical Connection Assembly Retainer,xe2x80x9d U.S. Pat. No. 5,641,940, presents a solution to the problems of rapid installation, positive retention, and economical manufacturing. The ""940 patent discloses a self-anchoring poke-through electrical connection assembly retainer, as well as a pre-formed intumescent material structure which is easy to apply during the manufacturing process.
However, problems still remain with the use of poke-through devices. One such problem involves the limited number of electrical interfaces provided by the prior art devices. It will be recognized that the size of the hole which may be drilled through a concrete floor is limited by the structural characteristics of the floor. Typically, building codes allow the drilling of a hole having a diameter between about two and four inches, which thus limits the maximum size of the poke-through device. However, even utilizing the mentioned four inch diameter hole, prior art devices only provide a limited number of electrical interfaces. For example, a single prior art poke-through device typically provides only a two-plug arrangement.
Although poke-through devices have succeeded in permitting removal of electrical power and communication lines from above-floor locations, all known poke-through devices still have outlet or connector boxes located flush with, or above, floor level. Heretofore, mounting of connectors below floor level, without an outlet or connector box located flush with, or above, floor level, has only been possible with complicated structures which must be pre-built or pre-cast into the floor, such as that disclosed in U.S. Pat. No. 3,864,883 to McMarlin.
U.S. Pat. No. 4,770,643 to Castellani et al. discloses a poke-through with an outlet which is generally flush with floor level. However, connectors plugged into the outlet are still above floor level and pose a tripping hazard. Such connectors are also prone to dislodgment by pedestrian traffic. More to the point, outlets and other electrical interfaces such as data connection jacks in flush devices are prone to damage from pedestrian traffic and/or placement and movement of furniture. For example, stepping upon or even temporarily placing a piece of furniture upon a data connection jack can permanently damage such jack.
There is therefore a need in the prior art for a concealed service poke-through device providing multiple electrical interfaces, and which permits mounting of electrical outlets or data connections jacks below floor level without an unsightly above-floor-level outlet or connector box which may pose a tripping hazard to personnel or interfere with placement of furniture on the floor and without a flush outlet which still leaves connectors exposed.
The present invention, which addresses the needs of the prior art, relates to a concealed poke-through device for installation in a hole in a floor structure. The floor structure defines a floor in a first working environment and a ceiling in a second working environment. The second working environment includes a junction box. The concealed poke-through device includes a body having upper and lower ends and which is sized for insertion within the hole. The upper end includes a generally circular receptacle-mounting region. The mounting region defines four substantially equal-size locating quadrants. At least one of the quadrants includes two electrical outlets. Finally, the lower end of the body communicates with the junction box whereby electrical power may be supplied to the outlets.
The present invention also relates to a recessed poke-through device for installation in a floor structure. The floor structure defines a floor in a first working environment and a ceiling in a second working environment. The second working environment includes a junction box. The recessed poke-through device includes a tubular body having upper and lower ends and which is sized for insertion within the hole. The upper end defines an interface mounting region. The lower end is adapted to electrically communicate with the junction box. The poke-through device also includes an intumescent sleeve surrounding the body. The poke-through device further includes an electrical interface mounted in the interface mounting region. The interface has an upper surface facing the floor. The upper surface is spaced a distance below the floor. Finally, the poke-through device includes a cover assembly including a floor plate and at least one access door. The door is movable between a closed position wherein the interface is enclosed within the device and an open position wherein the interface may be accessed through the hole. The door has an inner surface which defines a plane parallel to the upper surface when the door is in the closed position. The upper surface of the interface is recessed a distance below the plane of the door when the door is in the closed position whereby application of forces to the closed door does not transfer forces to the interface.
The present invention further relates to a concealed poke-through device for installation in a hole in a floor structure. The floor structure defines a floor in a first working environment and a ceiling in a second working environment. The second working environment includes a junction box. The concealed poke-through device includes a body having upper and lower ends and which is sized for insertion within the hole. The lower end communicates with the junction box. The poke-through device also includes a spacer secured to the upper end of the body and which defines an interface mounting region. The poke-through device further includes a plurality of electrical interfaces mounted in the interface mounting region. The electrical interfaces are selected from the group consisting of electrical outlets and data jacks. Finally, the spacer includes a channel extending across the center of the spacer for receiving electrical wires from a first electrical interface located on a first side of the mounting region and for directing the wires to a second side of the region opposite the first side.
The present invention additionally relates to the combination of a floor structure and a recessed poke-through device. The floor structure includes upper and lower surfaces defining a floor thickness and having a poke-through receiving hole formed therein. The receiving hole extends in a direction generally perpendicular to the upper and lower surfaces. The recessed poke-through device includes a body having upper and lower ends and which is sized for insertion within the hole. The upper end defines an interface mounting region. The lower end is adapted to electrically communicate with the junction box. The poke-through device also includes an electrical interface mounted in the interface mounting region. The interface has an upper surface facing the floor. The poke-through device further includes a cover assembly including a floor plate and at least one access door. The door is movable between a closed position wherein the interface is enclosed within the device and an open position wherein the interface may be accessed through the hole. The door has an inner surface which defines a plane parallel to the upper surface when the door is in the closed position. The upper surface of the interface is recessed a distance below the plane of the door when the door is in the closed position whereby forces applied to the door are not transferred to the interface. Finally, the interface is retained in the receiving hole at a distance below the upper surface of the floor structure which is sufficient to prevent the interface, and a typical connector secured thereto, from interfering with objects and persons located on the upper surface of the floor structure.
Finally, the present invention relates to a method of assembling a poke-through device for insertion in a hole in a floor structure. The method includes the step of providing a body having upper and lower ends and sized for insertion within the hole. The body defines an interior volume. The method includes the additional step of filling at least a portion of the interior volume of the body with a liquid intumescent material which thereafter sets and hardens within the body. The method includes the further step of forming at least one passage through the hardened material. Finally, the method includes the step of securing a first electrical interface having a first set of electrical wires extending therefrom to the upper end of the body and routing the first set of wires through the passage.
As a result, the present invention provides a concealed service poke-through device. The device permits an electrical interface, such as an outlet or data jack, to be located below floor level, such that unsightly and dangerous above-floor outlet boxes or connector boxes are not required, and such that connectors themselves may also be safely located at least substantially below floor level.